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The Single UNIX &reg; Specification, Version 2<br>
Copyright &copy; 1997 The Open Group

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<h4><a name = "tag_000_008_471">&nbsp;</a>NAME</h4><blockquote>
setregid - set real and effective group IDs
</blockquote><h4><a name = "tag_000_008_472">&nbsp;</a>SYNOPSIS</h4><blockquote>
<pre><code>

#include &lt;<a href="unistd.h.html">unistd.h</a>&gt;

int setregid(gid_t <i>rgid</i>, gid_t <i>egid</i>);
</code>
</pre>
</blockquote><h4><a name = "tag_000_008_473">&nbsp;</a>DESCRIPTION</h4><blockquote>
The
<i>setregid()</i>
function is used to set the real and effective group IDs of the calling
process.  If <i>rgid</i> is -1, the real group ID is not changed; if <i>egid</i> is
-1, the effective group ID is not changed.  The real and effective group IDs may be set
to different values in the same call.
<p>
Only a process with appropriate privileges can set the real group ID and the
effective group ID to any valid value.
<p>
A non-privileged process can set either the real group ID to the saved
set-group-ID from 
<i><a href="exec.html">exec()</a></i>,
or the effective group ID to the saved
set-group-ID or the real group ID.
<p>
Any supplementary group IDs of the calling process remain unchanged.
</blockquote><h4><a name = "tag_000_008_474">&nbsp;</a>RETURN VALUE</h4><blockquote>
Upon successful completion, 0 is returned.  Otherwise,
-1 is returned and <i>errno</i> is set to indicate the error and neither of
the group IDs will be changed.
</blockquote><h4><a name = "tag_000_008_475">&nbsp;</a>ERRORS</h4><blockquote>
The
<i>setregid()</i>
function will fail if:
<dl compact>

<dt>[EINVAL]<dd>
The value of the <i>rgid</i> or <i>egid</i> argument is invalid or out-of-range.

<dt>[EPERM]<dd>
The process does not have appropriate privileges and a change other than
changing the real group ID to the saved set-group-ID, or changing the effective group ID
to the real group ID or the saved group ID, was requested.

</dl>
</blockquote><h4><a name = "tag_000_008_476">&nbsp;</a>EXAMPLES</h4><blockquote>
None.
</blockquote><h4><a name = "tag_000_008_477">&nbsp;</a>APPLICATION USAGE</h4><blockquote>
If a set-group-ID process sets its effective group ID to its real group ID, it can still
set its effective group ID back to the saved set-group-ID.
</blockquote><h4><a name = "tag_000_008_478">&nbsp;</a>FUTURE DIRECTIONS</h4><blockquote>
None.
</blockquote><h4><a name = "tag_000_008_479">&nbsp;</a>SEE ALSO</h4><blockquote>
<i><a href="exec.html">exec</a></i>,
<i><a href="getuid.html">getuid()</a></i>,
<i><a href="setreuid.html">setreuid()</a></i>,
<i><a href="setuid.html">setuid()</a></i>,
<i><a href="unistd.h.html">&lt;unistd.h&gt;</a></i>.
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UNIX &reg; is a registered Trademark of The Open Group.<br>
Copyright &copy; 1997 The Open Group
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